1. Field of the Invention
The present invention is directed generally to the art of building construction and more specifically to panels constructed of glass blocks.
2. Description of the Invention Background
Glass blocks have been widely used for decades in the construction industry as partitions, exterior walls, and windows in buildings of all kinds. Glass blocks are typically formed by fusing together two pieces of glass. The seam where the two pieces of glass are fused together is centrally located along the top, bottom, and two side edges of the glass block. The seam is characterized by an upwardly extending ridge which gives the edges of glass blocks their unique profile.
Glass blocks are assembled in panels using a variety of assembly techniques. However, those techniques can be broadly categorized as mortar, and mortarless techniques. Techniques involving the use of mortar result in a panel of glass blocks which is assembled at the construction site or preassembled in a workshop by mortaring courses of glass blocks together much in the same way that courses of clay brick are mortared together. Unfortunately, the nonporous, nonabsorbent surfaces of the edges of glass blocks do not permit the formation of as strong a bond with the mortar as is the case with clay brick. Accordingly, those of ordinary skill in the art have sought ways to develop a stronger bond between the mortar and the glass blocks. Such efforts have led to the roughening of the edges, the application of resinous coatings to the edges, or the incorporation of special ingredients to the mortar in an effort to enable the mortar to form a stronger bond with the glass blocks.
As with the laying of bricks, the construction of glass block panels using mortar requires the talents of a skilled artisan. If the mortar is not of a uniform thickness, the glass blocks will not be properly laid and the resulting panel may be of uneven dimension. Also, the use of mortar is accompanied by dust and dirt in the construction area. Another drawback of glass block panels assembled with mortar is that the panels may not be assembled too quickly. Otherwise, the weight of the glass blocks will tend to squeeze the mortar out from between the lower courses. Thus, the construction of a mortared glass block panel is a time consuming task which requires substantial skill.
To overcome the drawbacks of mortared glass block panels, mortarless panels were developed. Mortarless panels are typically characterized by a spacer interposed between each of the glass blocks. The spacer ensures uniform spacing between the blocks. The spacer is typically of a width which is less than the width of the glass blocks such that a grid of troughs or grooves is formed when the glass blocks are assembled in a panel. The troughs or grooves are filled with some type of sealant which binds adjacent blocks together and usually keeps out humidity.
An example of the foregoing type of mortarless glass block panel is disclosed in U.S. Pat. No. 2,239,537. The spacer member disclosed in that patent is a metal plate which carries spaced resilient flanges. The resilient flanges form the trough between adjacent glass blocks which is filled with a mastic or other suitable caulking compound.
Another example of a mortarless glass block panel is disclosed in U.S. Pat. No. 4,058,943. Disclosed in that patent is a spacer member formed of wood or plastic. The width of the spacer member is dimensioned to provide a groove between adjacent glass blocks. The groove is partially filled with a filler bar, and the remainder of the groove is filled with a silicone caulking material which adheres to the spacer member to provide a chip resistant, mortar-like joint. The glass block panel may also be held together by a band tightly circumscribing the perimeter of the glass block panel.
Another example of a mortarless glass block panel is disclosed in U.S. Pat. No. 4,986,048. Disclosed in that patent is a spacer having a particular cross-section adapted to engage the edges of adjacent glass blocks at particular points. The width of the spacer is such that a groove is provided between adjacent glass blocks. The groove is filled with a translucent or colored silicone caulking which cures and sets to rigidify the glass block panel.
Although mortarless glass block panels avoid the drawbacks of traditional mortared glass block panels, mortarless glass block panels have drawbacks of their own. The spacers used in some mortarless glass block panels are unduly heavy and rigid thus adding unnecessary weight to the glass block panel. Other spacers provide only limited support. Still others are comprised of several parts which make it cumbersome to assemble the glass block panel. Accordingly, the need exists for a mortarless glass block panel which provides the desired degree of rigidity without adding undue weight to the glass block panel and which can be easily and quickly assembled by relatively unskilled workers, while giving the glass block panel much structural strength.